Tow vehicle for water-skiers



Feb. 21, 1961 L. S. SIMPSON TOW VEHICLE FOR WATER-SKIERS 2 Sheets-Sheet 1 Filed June 18, 1956 A mum m mm m Mn m Wm H J I5 6 0 7 E MWM H B AI; f w

Feb. 21, 1961 s. SIMPSON TOW VEHICLE FOR WATER-SKIERS 2 Sheets-Sheet 2 Filed June 18, 1956 INVENTOR. LE5 5. SIM/ 50 BY fl .A'ZTQKNEY United States Patent 2,972,326 TOW VEHICLE FOR W ATER-SKIERS Lee S Simpson, Alameda, Calif.

(440 N. Cornelia, Fresnofi, Calif.)

Filed June 18, 1956, SerQNo. 592,186

13 Claims. (Cl. 1156.1)

An important object of the invention is to provide a self-powered and regulated water-ski tow unit that is remotely operated and controllable by a person in the mere act of being towed thereby and without the manipulation of any mechanical means by the hands of the skier.

Another object of the invention is to provide avyaterski power 'unit completely enclosed in a small hull for protection from water damage from spray or capsizing. Another-object of the invention is to provide a power unit strong enough to start and to tow a water-skier and as versatile therefor as the conventional type motorboat. 1

Another object of the invention is to provide a watercraft for towing wherein the water-skier or other person being towed can steer the vehicle. g

' Another object of the invention is to provide controls for a towing watercraft so that a water-skiermay start, stop, and steer the craft while at any distaneebehind the craft, the distance depending only on the length of the tow ropes.

Another object of the invention is "to provide "controls that afford safety to the water-skier should be fall or otherwise wish to stop the craft.

i 'Ano'ther object of the invention is to provide automatic controls that respond immediately to stop, thecifaft when the water-skier falls his skis or otherwise actuates the controls. 7

Another object of the invention is to incorporate an additional safety device that automatically shuts off all powei should the skier fall or let goof 'the tow bar or shouldthe stopping mechanism fail to operate.) I

A still further object of the invention is to provide a suitable control handle tobe gripped by "the skiers hands at the free end of the tow lines, the handle being of one piece light weight material with no mechanical or moving parts yet is so equipped as to enable the s "er to s'tar't,--driv'e, stop, and steer the craft. a

Another object of the invention is to provide "priein mane controlsfor operating a r'notor of conventional type contained in atowing vehicle, so that it may be operat'ed and controlled from the free end of the usual weight or flexibility thereof.

2 Other objects and advantages of the invention will appear from the following description of a preferred embodiment thereof presented in accordance withi3'5 U.S.C.ll2. 7 l i v 'light weight tow line without noticeably increasing the "ice vehicle whose hull contains a motor sealed therewithin and protected from the water, spray, and leaks, together with a remote control device linked to the motor through tow ropes and a control tube operating pneumatic valves to stop and start the motor. An important feature of the invention resides in the pneumatically operated means for actuating the throttle valve and gearshift lever of the motor by means of the water-skiers thumb restricting or releasing a small supply of air directed to him through the control tube.

In the drawings:

Fig. 1 is a view in elevation showing a watercraft embodying the principles of the invention in use for towing a water-skier.

Fig. 2 is an enlarged view in elevation and in section of the watercraft of Fig. 1, taken along the line 2-2 in Fig. 3.

Fig. 3 is a top plan view of the same with the hatch cover. removed, and showing the motor and the tow ropes, control tube, and control handle, the ropes and tube being broken in the middle to conserve space.

Fig. 4 is a diagrammatic view of the pneumatic control circuit. The control valve is shown in its open position.

Fig. 5 is a view of the control valve of Fig. 4 shown in its closed position.

' Fig. 6 is an enlarged fragmentary plan view, partly in section, of the steering control.

' Fig. "7 is a view in elevation and in section of the elements. shown in Fig. 6. i

As shown in the drawings, the tow vehiclecomprises 'af boat-like craft 10 with a hull 11 in which is mounted "a motor 12, "such as an outboard type mo tor ora suitable inboard-type motor, whoseprop'ell'er housing 13 projects throughthe keel 14, being sealed'thereto bya suitable gasket 1'5 so that 'there will be no leakage. The upper portion of the hull 11 is closed by a deck 16 and a hatch 17 that protects the interior of the hull and the motor 12 from water and can be opened to give access to them. A steering rudder 18 extends below the keel 14 near the stem 19 and is controlled through a steering bar 20 which extends up into the hull 11. v w H v A water-skier '21 may ride on his skis 22 behind the craft 10; that he is driving by merely holding'o'nto a con trol handle 23 to which are attached the free ends of two ropes 24, 25.. The handle 23 is made so as to float on the water when dropped, since sinking would make its recovery more difficult. It may comprise a Wooden,

plastic, or hollow light metal member provided with suit able handheld openings 26, suitable means for anchor 'ing or securing the ropes 24, 25, and a centrally located bore 27 with an opening 28 at one end adjacent at least one ofthe handhold openings 26 which is gripped by a hand of the skier and the port or opening. 28 thus merely covered or opened as the towing .condition demands. The opposite end of the bore 27 communicates with and is connected to a flexible tubing 30 (e.g., rubber or plastic) which by changing the pressure therein is used to controlthe operation of the motor 12 controls of Figs, 3 and 4; Preferably,the tubing 30 is clipped to one of the-tow ropes '24, '25 to be coextensive therewith for its own protection. 5

The motor 12 is preferably an internal combustion e'n-.

gine mounted in the hull 11 approximately one-third the distance between the stem 19 and the bow. This engine is geared to a small compressor 31, which pumps air into a receiving tank 32, the tank 32 in turn being connected is) two parallel pressure-reducing valves 33, 34.- (See ig.j4.)- V 1 I 4 The first pressure-reducing valve 33 'is preferably actu- V I ated at about 1 7 p.s.i.a. to permit air to pass therethrough .1 Basically, theinvention comprises "a watertight water and througlia conduit 35 'to an air-relay valve 36 through -2,912,s2e I an inlet port 37. When this master relay valve 36 is in its open position (Fig. 4), its main outlet port 38 is open and a second outlet port 39 is closed by a valve member 40. When the valve is in this position, air passes through conduits 41 and 42 to the gearshift control cylinder 43 via a chcckrvalve 44. The air which enters the gearshift control cylinder 43 moves the spring-pressed piston 45 out against the pressure of a spring46, and this actuates the gearshift lever (not shown) for the motor 12. The air under pressure then passes from the cylinder 43 through a conduit 47 to a needle valve 48 and from there slowly passes to and builds up in a throttle control cylinder 50 where it then moves a throttle control piston 51, which is normally held closed byits spring 52. The needle valve 48 assures engagement of the gears before the throttle is moved, and helps build the speed up slowly. The cylinder 50 is also connected to the conduit 41 by a conduit 53 and a check valve 54. The check valve 54 4 then acts to' ground out the ignition for the engine 12, thereby stopping the boat.

In operation, the water-skier 21 puts the boat 10 into the water, turns on its ignition (if any) and starts the motor, and gets into the water himself on his skis 22 with the handle 23 in his hand. When he is ready to go, he puts his thumb over the port 28. Pressure builds up in the line 30 and opens the relay valve 36. Air then passes through the inlet 37 of the valve 36 through its power outlet 38 through the conduits 41 and 42, and the check valve 44, into the gearshift cylinder 43, to actuate the piston 45 therein and engage the gearshift. Also, as the pressure builds up, the air passes through the needle valve 48 into the throttle cylinder 50 and, by moving prevents air from passing into the throttle control cylinder 50 directly from the control valve 36 and forces it to first pass through the gearshift control cylinder 43. This means that the gears are engaged before the throttle is opened. When the valve member 40 shuts off the passage between the inlet 37 and the main outlet 38, a passage- Y way 55 bleeds ofi the conduit 41 through the outlet 39.

will flow more slowly from the gearshift cylinder 43 to the throttle cylinder 50 and out, so that the engine will first be slowed down and will be thrown outof gear when the engine is idling, the Whole taking place rapidly, i.e., within about three seconds. In fact,the slowing down is practically instantaneous. v

The relay valve 36 is opened and-closed by air from the second reducing valve 34, preferably at about 7 p.s.i., which first travels through a restricting needle valve 60. This relay valve 36 operates by air in opposition to a spring 61 moving a valve body 62 when the air pressure through an inlet 63 reaches about 6 p.s.i. Moreover, the valve body 62 simultaneously moves the valve member 40. When the water-skier restricts the air from passing out through the tube and opening 28, closing his thumb over the port opening 28, the pressurein a line 64 remains above about 6 p.s.i., and the relay valve 36 is held open. When he removes his thumb, which will necessarily happen if he falls'off, the port 28 is opened, andthe. air pressure drops. As soon as it drops .below:6

p.s.i. the spring 61 moves the valve body 62 to its closed position. Air from the throttle cylinder 50 and, later, from the gear cylinder 43 is quickly bled to the atmosphere'through the opening 39. As a result, the throttle is moved to ,its slow position andv the motor is then thrown out into neutral. 7

The skier controls the steering of thecraft 10 by swinging the handle 23 to the left or right to make a turn. The pressure is transmitted through the tow lines 24 and 25, which may really be a single rope, over sheaves the piston 51, causes the engine to speed up. The vehicle is then propelled by the propeller 85 and it continues to run until the skier 21 removes his thumb from the hole 28. When he does this, the pressure drops in the line 30, causing the control valve 36 to close and to open its third outlet opening 39. Air then flows from the throttle cylinder 50 through the check valve 54, conduit 41, and in through first outlet 38 to the second outlet 39, slowing down the boat 10. Air from the gearshift cylinder 43 flows through the needle valve 48 and joins the air in the throttle cylinder 50 to accomplish the same thing. Thus, the device is slowed down immediately and is thrown out of gear as soon as it has been slowed down. Actually, it will go only a few feet before stopping.

7 By turning the handle23 to the left or right, the tow ropes 24, 25 are moved. The tow ropes 24, 25 are pulled around the steering quadrant 72 so as to turn the rudder 18 to the right or left, depending on the direction to I which the handle 23 has been turned. Should the skier I fall and some restriction in the line 3% keep it closed,

the boat would continue to build up speed without load; the, safety switch 80 is actuated by pressure from the pickup 81 in the water, and, being actuated, grounds out the ignition and stops the engine.

' To those skilled in the art to which this invention relates, many changes in construction and widely dilfering embodiments and applications of the invention will suggest themselves without departing from the spirit and scope of the invention. The disclosures and the description herein are purely illustrative and are not intended to 70 and 71 and around a steering quadrant or pulley 72,

straight-ahead position and to return it there upon relaxation of the steering ropes 24, 25.

For additional safety, a special pressure switch 80 may be supplied below the keel 14. This switch 80 .is set to close at a predetermined pressure on its pickup 81 caused by excess speed, which can only occur when the boat 10 runs away without any load. This switchSQ be in any sense limiting.

. I claim:

" 1. A watercraft for towing a water-skier and the like, including in combination, a hull, a first source of power including anengine mounted on said hull and adapted to propel it, a rudder for said hull, a tow-rope connected to said rudder for turning it, a flexible, lightweight, buoyant pneumatic tube connected to said tow rope for most of its length a handle connected to the free end 'of saidtow-rope and to one normally open end of said tube and cooperating therewith for steering and controllingthe speed of said watercraft at a point remote from said hull, a second source of power, pneumatic means connected to said second source of power mounted on said hull ,andconnected to the other end of said tube andresponsive to pressure conditions within said tube for engaging and disengaging said engine to propel and stop propelling said hull and for speeding up said engine after engagement and for slowing it down before disengagement, depending on whether the free end of said tube end at saidhandle is opened to the atmosphere orclosed oiftherefrom, (and said pneumatic means including a single valve control means responsive to pressure.

2. .The combination of claim 1 wherein said second source of power comprises. a compressor, a pair of reduction valves, said valve control means being opened and closed by air passing through one said reduction valve andin communication with saidtube, said valve control means when opened passing air from the other said reduction valve, and a pair of pneumatic cylinders operatively connectedto said valve control means' and ems-2t means for deactuating' said throttle before disengaging said gears. s

4. The combination of claim 3 wherein the means set forth therein comprise .a check valve in the connection from said valve control means to said one pneumatic cylinder, 2. reduced-area passage betweensaid cylinders, and a check valve leading fromsaidother cylinder back to said valve control means. 1 I

5. A watercraft including "in combination, a hull, an engine mounted therein and adaptedto propel it, a pneutherein operatively connected "to said throttle and normallyadapted to place said :throttle in idling position v but movable by air under 'pressure'to places-aid throttle in accelerating position; first pneumatic means for supplying air under .pressure; second pneumatic means for supplying air under "pressure; and control 'valve having a main inlet connected to said first pneumatic means, a first outlet, a 'second'outlet, a valve body operable by actuation of said second pneumatic means to move to a first position connecting said main inlet to said first outlet and, upon 'deactuationof said second pneumatic means to move [to a second position disconnecting "said main inlet from said first outlet and connecting together said first and second outletsya control handle with means matic tube having means for opening and closing one down before disengaging it, depending onfwhether said a tube one end at said handle is opened or closed, and a pressure-actuated switch adapted to ground out and completely stop said engine, said switch having an actuating member on the bottom of said hull adapted to throw said switch at a predetermined velocity.

6. A watercrafnincluding in combination 'a hull having a steering rudder; a control handle operatively connected to said rudder; a motor for driving said hull by a propellerand having a gearshiftand a throttle; a first pneumatic cylinder having first piston means therein operatively connected to said gearshift and normally adapted to placesaid gearshift in neutralpos'ition but movable by air under pressureto place said gearshift in gear-engaging position; a second pneumatic cylinder having second piston means therein operatively connected to said throttle and normally adapted to place said throttle in idling position but movable by air under pressure to place said throttle in accelerating position; first pneumatic means for supplying air under pressure; second pneumatic means for supplying air under pressure at a lower pressure than said first means; a control valve having a main inlet connected to said first pneumatic means, a first outlet, 21 second outlet, a valve body operable by actuation of said second pneumatic means to move to a first position connecting said main inlet to said first outlet and, upon deactuation of said second pneumatic means to move to a second position disconnecting said main inlet from said first outlet and connecting together said first and second outlets; means at said handle for alternately actuating and deactuating said second pneumatic means; means connecting said first outlet for free flow of air to said first pneumatic cyiinder through a check valve when said valve body is in said first position; means connecting said first and second pneumatic cylinders for restricted flow of air therebetween; and means connecting said second pneumatic cylinder for flow of air back to said first outlet through a check valve when said valve body is in said second position; whereby the actuating of said second pneumatic means at said handle causes the engagement of said gearshift and subsequent throttling of said motor and the deactuating of said second pneumatic means causes the slowing down of said motor and subsequent disengagement of its gearshift.

7. A watercraft, including in combination a hull; a motor for driving said hull by a propeller and having a gearshift and a throttle; a first pneumatic cylinder having first piston means therein operatively connected to said gearshift and normally adapted to place said gearshift in neutral position but movable by air under pressure to place said gearshift in gear-engaging position; a second pneumatic cylinder having second piston means for alternately actuating anddeactua'ting said second pneumatic means; means connecting said first outlet for free fiowof air to said first pneumatic "oylind'er'throu'gh acheck valve when said valve body'is in said first position; means connecting said first and secondpneumatic "cylinders for restricted flow of air therebetween; and means connecting said second pneumatic cylinder for flow of air back to said first outlet through a check valve when "said valve body is in said second position; whereby the actuating of said second pneumatic means at said handle causes the engagement of said gearshift and subsequent throttling of said motor and the deactuating of said second pneumatic means causes the slowing down of said motor and subsequent disengagement of its gearshift.

8. A watercraft, including in, combination a hull; a motor for driving said hull by a propeller and having a gearshift and a throttle; a rudder for steering said hull; a pulley rigidly connected to said rudder; a control handle that floats on water; rope means passing around said pulley and connected to said handle for'steerin'g said rudder by rotating said .pulley when said handle is turned; a first pneumatic cylinder having first piston means therein operatively connected to said gearshift and urged by first spring means to normally place said gearshift in neutral position but movable by air under pressure to place said gearshift into gear-engaging position; a second pneumatic cylinder having second piston means therein operatively connected to said throttle and urged by second spring means to normally place said throttle in idling position but movable by air under pressure to place said throttle into an accelerating position; first pneumatic means for supplying air under pressure; second pneumatic means for supplying air under pressure at a lower pressure than said first means; a control valve having a main inlet connected to'said first pneumatic means, a first outlet, at second outlet, a valve body movable between a first position connecting said main inlet to said first outlet and a secondposition discon necting said main inlet from said first outlet and connecting together said first and second outlets, third spring means weaker than said second pneumatic means normally urging said valve body to said second position, and an auxiliary inlet connected to said second pneumatic means for moving said valve body in opposition to said third spring means; means at said handle for bleeding off said second pneumatic means, so that said third spring means moves said valve body into said second position and for blocking said bleeding so as to build up pressure in said control valve auxiliary inlet and move said valve body to said first position; means connecting said first outlet for How of air to said first pneumatic cylinder through a check valve when said valve body is in said first position; means connecting said first and second pneumatic cylinders through a needle valve; and means connecting said second pneumatic cylinder for flow of air back to said first outlet through a check valve when said valve body is in said second position; whereby the blocking of said second pneumatic means at said handle causes the engagement of said gearshift and subsequent throttling of said motor and the bleeding-01f of said "7 second pneumatic means causes the slowing down of said motor and subsequent disengagement of its gearshift.

9. In a self-propelled ski-tow having a platform, speed adjustable first motive power means mounted on said platform, traction means also mounted on said platform, and adapted to be operated by said first motive power means for propelling the ski-tow; a movable control device on said platform having actuating means normally biased to adjust said first motive power means to a low speed, a second Source of motive power on said platform, a flexible tow-line connected to and extending rearwardly of said platform and including a hand hold portion, and a flexible control means coextensive with said towline connected at its end adjacent said platform to said movable control device, the opposite end of said flexible control means being connected to said hand hold portion and having means operative upon manual engagementof said hand hold portion to actuate said movable control device to cause said secondsource of motive power to actuate said actuating means to move same against its bias to adjust said motive power means to a high speed, and to disconnect said second power source to actuate said actuating means to said low speed upon manual disengagement of said hand hold portion.

10. In a self-propelled ski-tow according to claim 9, in which the ski-tow is a water-borne craft and has a pressure sensitive device projecting from the craft into the water for discontinuing operation of the motive means in response to a predetermined water-pressure due to an abnormal speed of the craft.

11. In a self-propelled ski-tow having a platform, speed adjustable motive power means mounted on the platform and traction means operated by said motive power means for propelling the ski-tow; a fluid pressure operated control device on the platform normally biased to adjust the motive power means to a low speed, a second source of power including a fluid pressure source mounted on said platform, a flexible tow-line connected to and extending rearwardly of the platform and havinga hand portion, a flexible hollow conduit coextensive with the tow-line and coupled'at the end adjacent the platform to said fluid pressure source and to said control device, the opposite end of said conduit being connected to said hand portion and said hollow conduit having an opening therein adjacent said hand portion for relieving the fluid pressure build-up by the pressure source when unobstructed and for providing pressure build-up in the hollow conduit upon manual obstruction by the skier, to operate said control device to increase the speed of the motive means.

12. In a self-propelled ski-tow according to claim 11 including clutch elements between the motive and traction means normally biased into disengagement and a second hydraulic-pressure operated control device connected to the hollow conduit for moving the clutch'elements into engagement upon build-up of pressure in the hollow conduit. 1 .7

13. In a self-propelled ski-tow according to claim 11 in which the ski-tow is a water-borne craft and pressuresensitive means extending from the platform into the water for rendering the motive means inoperative in response to water-pressure in excess of a predetermined value upon abnormal increase of speed of the motive means and the craft.

References Cited in the file of this patent UNITED STATES PATENTS 1,814,772 Sterling July 14, 1931 1,893,994 Johnson Jan. 10, 1933 7 2,404,951 Donaldson July 30,1946 2,451,781 Steele Oct. 19, 1948 2,593,806 Steele Apr. 22, 1952 2,776,443 Howard Jan. 8, 1957 

